Indeed, thin is the examplar given in Wikipedia for /θ/. It also has further explanation of th is sometimes voiced and sometimes unvoiced depending on context.

Indeed, thin is the examplar given in Wikipedia for /θ/. It also has further explanation of th is sometimes voiced and sometimes unvoiced depending on context. One thing to note is that some English speakers pronounce /ð/ and /θ/ as allophones, likely due to their identical orthography. At the beginning and middle of words, it becomes voiced /θɪn/ and /θɪŋ/ (thin and thing) becoming /ðɪn/ and /ðɪŋ/, respectively. At the end of words, it remains unvoiced. https://en.wikipedia.org/wiki/Voiceless_dental_fricative https://en.wikipedia.org/wiki/Voiceless_dental_fricative th-fronting always catches my attention as well: https://en.wikipedia.org/wiki/Th-fronting https://en.wikipedia.org/wiki/Th-fronting